Dynamically I created ASP.NET user control using ASP.NET Ajax and Web Service

Dynamically I created ASP.NET user control using ASP.NET Ajax and Web Service

but I got an error on onclick of the asp button

Error:

The state information is invalid for this page and might be corrupted. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: The state information is invalid for this page and might be corrupted.